(CN) – A fire department violated a firefighter’s free-speech rights when it restricted his ability to include religious comments in work emails and forums, the Washington Supreme Court ruled Thursday.

The fire department now has the burden of showing it would have fired the firefighter even without his protected First Amendment actions.

Jonathan Sprague was a captain for the Spokane Valley Fire Department, where he started a group of Christian firefighters.

Sprague used the department’s email to send messages about the Christian fellowship, which often incorporated Bible passages and topics to be discussed at meetings, according to court documents.

The fire department has a policy prohibiting using work email for personal uses, and it disciplined Sprague for including religious content in his emails.

Eventually, the department suspended and fired him after a mediation process failed.

Sprague claimed in state court he was the victim of religious discrimination and free speech violations.

A Spokane County judge found Sprague’s cause of action was barred by collateral estoppel, also known as issue preclusion, and found in favor of the department.

In 2016, an intermediate appeals court upheld the decision, finding that Sprague’s claims were precluded by previous findings made by the county’s civil service commission.

In a lengthy dissent that begins with a Bible quote, Judge George Fearing argued that the department’s ban on Sprague’s evangelism was “viewpoint discrimination.”

The fire department used its email system “in part, as a bulletin board,” Fearing wrote in his 35-page dissent, and noted that the department’s insurer used it to send newsletters about topics like suicide prevention, binge drinking, and eating disorders, though through a secular lens.

“Both the newsletters and Jonathan Sprague’s missives mentioned suicide and how to prevent suicide,” Fearing wrote. “A newsletter spoke of depression. Arguably, Sprague also mentioned coping with depression. The fire department’s topic of team building may overlap with Sprague’s lecture on leadership.”

Sprague petitioned the state Supreme Court, which ruled 5-4 Thursday that the fire department had indeed engaged in viewpoint discrimination, in violation of his First Amendment rights.

“Permitting equal access to a forum does not endorse religion,” Justice Charles Wiggins wrote for the majority, while noting that the fire department’s policy was reasonable.

The panel concluded that Sprague spoke as a citizen, and the disputed emails were not sent as part of his work duties, and that some of his emails dealt with issues of public concern, such as suicide and mental health.

The department selectively applied its policy in a way that precluded Sprague from expressing his religious views, the panel found. Further, its interests as an employer did not outweigh Sprague’s interest in speaking.

“Sprague solicited feedback from his coworkers, including information from those who did not wish to receive the emails,” Wiggins wrote. “In fact, one employee requested to be removed from the list, and Sprague removed him.

“The facts simply do not support [the department’s] contention that Sprague’s position as captain coerced other employees to participate in religious activities.”

The panel also rejected the lower court’s conclusion that collateral estoppel did not bar Sprague’s lawsuit.

The civil service commission did not make a decision about whether the department violated Sprague’s free speech rights, and those issues have yet to be properly evaluated, the panel concluded.

“Applying collateral estoppel to Sprague’s claims in these circumstances creates a negative incentive for terminated public employees to forgo their administrative remedies before the commission out of fear they will be unable to receive other remedies available from the court,” Wiggins wrote.

On remand, Wiggins ordered the court to determine if Sprague’s firing was justified in spite of the First Amendment violation.

In a brief 3-page partial dissent, Justice Mary Yu questioned whether the department had an unwritten policy or practice that discriminated against religious viewpoints like Sprague’s.

“The majority’s dismissive treatment of SVFD’s position suggests a view that using government resources to promote specific religious concepts is entirely appropriate, and that any attempt by a government employer to regulate such activity is unconstitutional,” Yu wrote, joined by three colleagues